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16 November 2015, Science Daily, Bird decline shows that climate change is more than just hot air. Scientists have long known that birds are feeling the heat due to climate change. However, a new study of a dozen affected species in the Western Cape suggests their decline is more complex than previously thought — and in some cases more serious. According to the study, published in Conservation Physiology, by scientists from the Percy Fitzpatrick Institute at the University of Cape Town and Nelson Mandela Metropolitan University, there could be several reasons why birds are being negatively affected by human-made climate change. They suggest that contrary to expectations the birds’ heat tolerance — or lack thereof — is not necessarily the main factor chasing species out of their preferred habitat. Other factors like changing fire and rainfall patterns, and new bird behaviour patterns could also be responsible for the decline, according to the study which includes some well-known species such as the Malachite Sunbird and the Familiar Chat. Lead researcher Susie Cunningham says a better understanding of how climate change affects bird species could help develop conservation strategies to increase chances of survival: “We know climate change is linked to changes in species’ numbers and distributions, but we don’t always know exactly how or why,” Cunningham says. “We need to figure out the factors actually driving declines before we can develop proper conservation measures to halt them.” Read More here

14 November 2015, Climate News Network, Greenland glaciers’ melting speeds up again. The increasing rate at which Greenland’s glaciers are melting this century has confounded polar scientists. A massive Greenland glacier that holds enough water to raise sea levels by half a metre is melting at speed, according to a new study. The Zachariae Isstrom in northeast Greenland has entered a phase of accelerated retreat, and is losing mass at the rate of 5 billion metric tons a year, according to US scientists. They report in the journal Science that a succession of aerial surveys combined with multiple satellite observations has established that the base of the glacier is being eroded rapidly by a mix of warmer ocean water and increasing amounts of meltwater from the surface of the Greenland ice sheet. “North Greenland glaciers are changing rapidly,” said Jeremie Mouginot, an earth system scientist at the University of California, Irvine, who led the study. “The shape and dynamics of the Zachariae Isstrom have changed dramatically over the last few years. The glacier is now breaking up and calving high volumes of icebergs into the ocean, which will result in rising sea levels for decades to come.” Read More here

10 November 2015, The Guardian, New insect arrivals signal radical climate change – we can’t say we’ve not been warned. The exotic species colonising the south coast are the experts when it comes to adapting and surviving. We should learn from them. Something stunning happened last week, which has never before occurred in Britain in November: a subtropical butterfly, the long-tailed blue, was seen flying on the south coast of England. Another unprecedented event took place one August evening: a volunteer at the Dungeness bird observatory was strolling home from the pub when he was transported to summer holidays on Mediterranean verandas – he heard the nocturnal whirring of tree crickets. Hundreds of these warmth-loving insects have now been found breeding in Britain for the first time. Exceptional insects are the new normal. The long-tailed blue is a common sight across Africa, south Asia and Australia. Very occasionally – in 1945 and again in 1990 – warm winds push a couple of dozen to Britain. In 2013, however, more than 100 individuals were spotted between Bognor and Dover. This year has seen another 60 mostly British-born specimens emerging spectacularly late in the year for any butterfly, let alone a subtropical creature. We struggle to act on climate change because it involves restraining consumption – of fossil fuel – and we as a species find it hard to practise restraint. We are also struggling because arguments focused on parts per million of CO₂ are abstract and remote from real experience. Insects could help us realise just how radically our climate is changing. Forgive an obvious animal cliche, but they are the canary in the coal mine. Along with tree bumblebees, another very visible newcomer in Britain, we might describe them as the first climate refugees to reach our shores. Read More here

10 November 2015, The Conversation, Ocean acidification: the forgotten piece of the carbon puzzle. Ocean acidification – the rise in ocean acidity due to the increased absorption of carbon dioxide (CO₂) – is often thought of as consequence of climate change. However, it is actually a separate, albeit very closely-related problem. Ocean acidification is often referred to as “the other CO₂ problem” because, like climate change, it is primarily a result of the increased emissions of this gas. Despite their common driver, though, the processes and impacts of ocean acidification and climate change are distinct. It should not be assumed that policies intended to deal with the climate will simultaneously benefit the oceans. The current emphasis of global climate policies on a warming target is a case in point. A narrow focus on temperature stabilisation, for example, opens the door for policy interventions that prioritise the reduction of greenhouse gases other than carbon dioxide. This is because non-CO₂ greenhouse gases — like methane and nitrous oxide, which can arise from agricultural and industrial processes — typically have a higher global warming potential and might even be less costly than CO₂ to reduce. In addition, several geoengineering schemes have been proposed to reduce the impacts of a warming climate. Yet such schemes often do nothing to address emissions, and may even exacerbate carbon absorption in the oceans. Read More here

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